Sustained weight loss seen even when GLP-1 availability is inconsistent

Key Takeaways:

• Even with inconsistent access to GLP-1 medications, people achieved substantial weight loss when treatment was combined with lifestyle interventions and coaching.
• Participants who experienced gaps in their GLP-1 treatment still saw an average weight loss exceeding 13% after one year.
• Consistent use of GLP-1 medications alongside lifestyle changes produced the most pronounced weight reductions, underscoring the value of an integrated approach.
  

Research underscores weight loss success despite gaps in GLP-1 treatment

Popular anti-obesity medications continue to deliver meaningful weight loss results, even when access is inconsistent, according to new research presented at ENDO 2025, the Endocrine Society’s annual meeting held in San Francisco, California. The findings were shared by Calibrate, a privately held weight-loss company based in New York.

Kaelen L. Medeiros, M.S., director of data and research at Calibrate, highlighted the difficulties many people face in maintaining uninterrupted treatment. “Patients taking GLP-1 treatments like semaglutide and tirzepatide often face challenges consistently accessing their medications due to supply shortages or insurance coverage obstacles,” she explained.

Impact of treatment interruptions

To explore how such interruptions might affect outcomes, researchers examined data from people enrolled in Calibrate’s commercial metabolic health programme. This programme integrates intensive lifestyle change with medical treatment, focusing on four key areas of metabolic health: food, exercise, sleep, and emotional wellbeing. Participants also benefited from personalised, one-on-one health coaching.

The study analysed records from 6,392 individuals living with overweight or obesity who had received at least one month of GLP-1 treatment and completed a minimum of one year in the programme. Among these, 72.5% experienced at least one disruption in their GLP-1 access, while 11.1% faced multiple disruptions. On average, participants received 8.13 GLP-1 prescriptions in the first year, increasing to 15.25 in the second year.

Weight loss outcomes across groups

Despite the access challenges, participants still achieved notable weight loss. After 12 months:

• Those who experienced interruptions in their medication saw an average weight reduction of 13.7%.
• Those without any treatment gaps achieved an average weight loss of 17%.
  

At 24 months, the figures rose to:

• 14.9% average weight loss for participants with treatment disruptions.
• 20.1% average weight loss for those with uninterrupted access.
  

Even participants who received only between one and four GLP-1 treatments over the course of a year achieved clinically meaningful weight reductions, losing over 10% of their body weight on average.

The role of lifestyle change and coaching

“While unpredictable GLP-1 medication access is frustrating, the good news is that our research shows effective weight loss can still be achieved if paired with appropriate lifestyle changes and coaching support,” said Medeiros.

She added, “Given the often-unpredictable availability and shifting insurance coverage associated with anti-obesity medications, it’s important that patients understand the significant impact that lifestyle changes and coaching paired with treatment can have on their health outcomes.”

Consistency remains the most effective approach

While the findings underscore that significant weight loss is possible even when GLP-1 medication use is inconsistent, Medeiros emphasised that a steady, uninterrupted course of treatment combined with comprehensive lifestyle support remains the most effective strategy.

This research provides further reassurance for people managing overweight and obesity that meaningful progress can be made even when medication access is not always predictable, particularly when combined with structured lifestyle interventions and personalised coaching.

CCH Insight:

This study shows that significant weight loss can be achieved despite an interrupted supply of GLP-1 medications, but not as much as with a continuous supply. Although the reporting emphasises the fact that participants received diet and lifestyle coaching, the study cannot make any conclusions regarding its impact, because all participants received the coaching – there was no control group without coaching for comparison. These medicines are meant to be used as an adjunct to diet and lifestyle advice, and outcomes are likely to be better when this is the case, but this study does not provide evidence to support that.